The present invention relates to optical displays and, in particular, to an optical display. A major objective of the present invention is to provide an optical display that emits bright visible-light.
Much modern technology is closely identified with the manufacturing and the applications of optical fibers. The main application of optical fibers is the transmission of light, which is based on the principle of total reflection of light rays. When a light ray traveling in an optical medium of refractive-index n.sub.1, strikes an interface with an optical medium of refractive-index n.sub.2, then the total reflection will occur if n.sub.1 is larger than n.sub.2 and an incident angle (measured to the normal of the interface) is larger than a 15 critical angle of total reflection. In this fashion, the light rays are repeatedly reflected within the optical medium of refractive-index n.sub.1 in the direction of transmission without loss of light energy.
An application of optical fibers is information display in which bare optical fibers are used. As optical fibers have a refractive index larger than that of air surrounding the optical fibers, the light into the bare optical fibers is transmitted forward in the bare optical fiber, and is refracted into air at an end of the optical fiber. In order to provide bright light, the end of the optical fiber is designed as convex in shape according to optical principle.
The use of such optical fibers allows light from a lighting source to be transmitted to remote and spaced locations where the light may be emitted as either a point or line of illumination. Because of the unique capability of optical fibers to transmit light, it is possible to create displays of light without having to provide a lamp or other light source at the point of display. Optical fibers have been utilized to create a variety of visual and ornamental displays which may take a sculptured or three dimensional form or may appear as points or lines of light along a viewing surface or panel.
U.S. Pat. No. 4,276,705 to Barth et al., "Barth" herein, involves graphic display means, and relates to an enclosure with a thin opaque cover made up of an outermost sheet of paper bearing a design, to serve as a display face. An underlying sheet of aluminum foil is backed by an aluminum screen. Incandescent lights are mounted within the enclosure to light its interior. Through the use of pointed markers made of transparent plastic, pinpoints of light can be spotted where desired on the display face for various purposes. The markers are exposed to light in the interior of the enclosure as they pierce the aluminum foil, and therefore show up as points of light on the display face.
Barth discloses a marker constructed from a light transmitting material, such as glass or one of the transparent or translucent plastics. Each mark has a substantially cylindrical shank, a tapered piercing tip and a spherical head. The aluminum screen retains the markers in position when they are pushed through the foil and to provide reinforcing support for the thin, flexible foil.
U.S. Pat. No. 4,860,475 to Levy et al., "Levy" herein, discloses an educational kit for teaching and developing the creative arts wherein each kit includes a frame in which one or more changeable panels, pictures or screens are selectively mounted and wherein the frame provides support for one or more bundles of optical fibers which may be illuminated by a light source also mounted within the frame. The kits further include color filters which are preferably in the form of color wheels adjustablly mounted with respect to the fiber optic bundles and the light source.
U.S. Pat. No. 2,051,288 to Thomas J. Curtis, "Curtis" herein, addresses an illuminated sign element that is formed of transparent material. In Curtis' preferred embodiment, the element has a substantially cylindrical body, a shoulder and a convex head. The external surface of both forward portion of the body and the head are etched or frosted.
Although the prior art acknowledges variety of optical-fiber displays using optical fibers, the applications of these optical-fiber displays are considerably limited because the optical fibers cannot provide enough light intensity compared to that of neon sign. The light intensity of the optical fibers may be improved by the use of light source with high power and/or the optical fibers with enlarged cross-section.
However, the cost of the optical-fiber display use of high power light source and/or optical fibers with enlarged cross-section is raised. The high power is also dangerous for operation and maintenance. In addition, because prior art optical fibers applied in optical display does not emit light actually, only change of the physical shape of optical fibers does not bring about any improvement of their light-emitting property of per unit area. Furthermore, the optical fibers with large cross-section bring into lower resolution of information display. Therefore, prior art optical-fiber display is not available to replace the neon sign.
Neon sign is commonly accepted in commercial display due to its brightness. However, a relatively high voltage, usually 3,000 v to 12,000 v, has to be applied to neon sign apparatus so as to activate the gas filled in the glass tubes of the neon sign apparatus. This high voltage generates very strong interference. With use of the gas filled glass tubes in the neon sign apparatus, the maintenance of neon sign becomes cumbersome. In addition, when a part of a neon sign is broken, the continuous tube of broken part has to be replaced, which significantly raises the cost of maintenance. The expensive cost of neon sign is also an obstacle to its application.
What is needed is an optical display with bright visible-light. In particular, an enclosed-light-reflective chamber and an intensive lighting source within the reflective chamber provide intensive light rays. Optical elements of predetermined shape and additive materials are provided to effectively collect the intensive light rays in the chamber. During light rays are transmitted through the body of each optical fiber, the additive materials in the optical elements is activated to emit or to scatter light so that the light intensity emitted from the optical elements is increased, thereby generating ultra-bright light.